A simple WINDOWS ONLY example using winsock to wake on lan WOL in C

WOL.c

//example mac: b1:27:eb:b4:a0:9e
//example hex mac: 0xb1, 0x27, 0xeb, 0xb4, 0xa0, 0x9e
//put example max in place of #define MAC, make sure to end with a , like shown below
//also update IP, and PORT if you need to

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include <winsock2.h>

#define IP	("192.168.0.1")				// IP to wake
#define PORT	(9)					// wake listen port
#define MAC	0xb1, 0x27, 0xeb, 0xb4, 0xa0, 0x9e,	// max address, have a ',' on the end


int main(int argc, char** argv)
{
	struct sockaddr_in si;
	SOCKET s;
	WSADATA wsa;
	int status;
	
	if(WSAStartup(MAKEWORD(2,2), &wsa) != 0) {
		fprintf(stderr, "Winsock boot failed : %d\n", WSAGetLastError());
		return 1;
	}
	
	puts("Winsock startup");
	
	if((s = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP)) == SOCKET_ERROR) {
		fprintf(stderr, "Failed to create socket : %d\n", WSAGetLastError());
		WSACleanup();
		return 1;
	}
	
	puts("Winsock socket creation");
	
	memset(&si, 0, sizeof(struct sockaddr_in));
	si.sin_family = AF_INET;
	si.sin_port = htons(PORT);
	si.sin_addr.s_addr = inet_addr(IP);
	
	puts("Winsock setup");
	
	char data[] = {0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC MAC};
	
	printf("Size of data: %Iu\n", strlen(data));
	puts("Data gen");
	
	status = sendto(s, data, strlen(data) - 1, 0, (struct sockaddr *) &si, sizeof(si));
	if(status == SOCKET_ERROR) {
		fprintf(stderr, "Failed to send message : %d\n", WSAGetLastError());
		closesocket(s);
		WSACleanup();
		return 1;
	}
	
	fprintf(stdout, "Sent WOL!\n");
	
	closesocket(s);
	WSACleanup();
	
	return 0;
}